Enter a Sh from (Monad)IO. The environment and working directories are
inherited from the current process-wide values. Any subsequent changes in
processwide working directory or environment are not reflected in the
running Sh.

named after bash -e errexit. Defaults to True.
When True, throw an exception on a non-zero exit code.
When False, ignore a non-zero exit code.
Not recommended to set to False unless you are specifically checking the error code with lastExitCode.

variadic argument version of run.
The syntax is more convenient, but more importantly it also allows the use of a FilePath as a command argument.
So an argument can be a Text or a FilePath.
a FilePath is converted to Text with toTextIgnore.
You will need to add the following to your module:

Environment directory

Change current working directory of Sh. This does *not* change the
working directory of the process we are running it. Instead, Sh keeps
track of its own working directory and builds absolute paths internally
instead of passing down relative paths. This may have performance
repercussions if you are doing hundreds of thousands of filesystem
operations. You will want to handle these issues differently in those cases.

Get a full path to an executable on PATH, if exists. FIXME does not
respect setenv'd environment and uses findExecutable which uses the PATH inherited from the process
environment.
FIXME: findExecutable does not maintain a hash of existing commands and does a ton of file stats

internal functions for writing extensions

find functions

List directory recursively (like the POSIX utility find).
listing is relative if the path given is relative.
If you want to filter out some results or fold over them you can do that with the returned files.
A more efficient approach is to use one of the other find functions.